AROTA
Piston Engine Schematic
An easy guide to visualize the workings of a typical aircraft piston engine

Note: This is a typical layout of a single engine piston, and some components may not be available/required by different manufacturers!
For example, some aircraft have primer and no choke or vice versa. The primer and choke work on different principles but serve the same purpose.
In some engines (such as Rotax), there is no mixture control as the mixture needle is connected to a membrane that automatically adjusts to atmospheric pressure
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Fuel tanks: Most light aircraft piston engines are fuel fed by gravity, assisted by engine-driven pumps
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Fuel selector: Displays the active fuel tank in use
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Auxiliary fuel pump: Manually activated fuel pump to increase fuel pressure during maneuvres/take-off/landings
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Engine-driven fuel pump: Connected to the camshaft and pumps fuel toward the carburetor
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Mixture control: Controls the fuel-to-air ratio to maintain the optimal engine efficiency at different altitudes
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Choke: Restricts air and enriches the fuel-to-air ratio for cold starts
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Engine primer: Sprays fuel into the piston cylinders and enriches the fuel-to-air ratio for cold starts
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Cylinder head temperature gauges: Thermocouples are installed in the cylinder to monitor the temperature
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Exhaust gas temperature gauge: Used alongside the mixture control to determine the optimum fuel-air mixture
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Carburetor heat: Auxiliary control to redirect exhaust air to melt ice in case of carburetor icing at the venturi or throttle valve

*These graphics are created by me and are free for educational use, but not for any form of monetization